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Multiscale windowed Fourier transform for phase extraction of fringe patterns
1Institute of Optoelectronic Engineering, Jinan University, China. tzjg@jnu.edu.cn
Applied Optics
|April 21, 2007
Summary
This study introduces a new multiscale windowed Fourier transform for precise phase extraction from fringe patterns. Combining windowed Fourier and wavelet transforms enhances accuracy compared to existing methods.
Area of Science:
- Optics and Photonics
- Signal Processing
Background:
- Phase extraction from fringe patterns is crucial for optical metrology.
- Existing methods often struggle with precision and adaptability to varying fringe characteristics.
Purpose of the Study:
- To develop an advanced phase extraction technique for fringe patterns.
- To improve the precision and robustness of phase extraction using a novel transform.
Main Methods:
- A multiscale windowed Fourier transform (MWFT) was developed.
- Window width control is automated using an instantaneous frequency gradient.
- Instantaneous frequency is determined via wavelet transform ridge detection.
Main Results:
- Numerical simulations validated the proposed MWFT method.
- Experimental results confirmed the technique's effectiveness.
- The combined Fourier and wavelet transform approach yielded higher phase extraction precision.
Conclusions:
- The multiscale windowed Fourier transform offers a precise method for fringe pattern phase extraction.
- Integration with wavelet transform significantly enhances accuracy.
- This technique provides a robust solution for optical metrology applications.
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